A cylindrical battery cell employs alternating electrode and electrolyte layers. Each electrode may include a current collector substrate and one or more electrochemically active layers. Among the considerations for the current collector design are the following: (a) high electrical conductivity; (b) resistance to corrosion by the electrolyte used; (c) resistance to electrochemical reactions so as not to be consumed too quickly; (d) mechanical strength and flexibility allowing it withstand manufacturing operations (e.g., pasting and rolling); (e) low overall cost, including material cost and manufacturing; and (f) a surface structure providing good physical contact, or “connectivity,” to the electrochemically active layers (e.g., the material should not form a passivating film so as to prevent the good physical contact and should adhere well to the electrochemically active layers). It is not critical that any one or more of these features be met. For example, a current collector may be outstanding in one or more categories and yet be sub-standard in others. Thus, a material having disadvantages in one aspect may still be used if the disadvantages may be overcome by the overall battery design. Common materials currently used for zinc negative electrode current collectors include copper and brass.
One way to evaluate cell performance and establish the relationship between features of the current collector and cell performance is to measure the gassing rate of current collector strips under conditions. During battery operation, gases such as hydrogen may be evolved. Although some evolved hydrogen may be recombine with oxygen to produce water, the remaining hydrogen would build up in the cell and may cause cell rupture or damage conductive pathways. It is desirable to design cell components that have low out-gassing rates.